......DE..ESFRGB..IT....NL........................RDIM360 - Ver 2.5 (21 Aug 1997) 2100000/00346837EUROPEAN PATENT SPECIFICATIONB119940713EP89110699.9198906131990122819921006enenen150944/8819880617JP199407131994281989122019895119940713199428199310215 5C 08L 23/16 A 5C 08L 51/06 B 5C 08L 77/00 BdeVulkanisierte Äthylen-Alpha-Olefin-Copolymer-Gummi-ZusammensetzungenVulcanized, ethylene/alpha-olefin copolymer rubber compositionfrComposition vulcanisée d'un caoutchouc d'un copolymère éthylène/alpha-oléfineEP-A- 0 034 704EP-A- 0 266 221GB-A- 2 052 528Tsuji, Mitsuji1-9, YushudainishiIchihara-shiJPUsuda, Eiichi10-7, Izumidai-3-chomeIchihara-shiJPAoshima, Masashi16-28, Higashioka-2-chomeIbaraki-shi OsakaJPSUMITOMO CHEMICAL COMPANY LIMITED00214342B4293/vo5-33, Kitahama 4-chome, Chuo-kuOsaka-shi, Osaka 541JPHenkel, Feiler, Hänzel & Partner00100401Möhlstrasse 3781675 MünchenDEDEESFRGBITNL19910206199106

The present invention relates to a vulcanized ethylene/α-olefin copolymer rubber composition, more particularly, a vulcanized ethylene/α-olefin copolymer rubber composition having a high hardness.

The vulcanized, ethylene/α-olefin copolymer rubber composition is excellent in weather resistance and thermal resistance as compared with natural rubbers and general-purpose rubbers such as styrene/butadiene rubber, butadiene rubber or isoprene rubber. Therefore, it is widely used for automobile parts, industrial parts or electric parts to make the most of its characteristics.

For some of the above-mentioned uses, the vulcanized, ethylene/α-olefin copolymer rubber composition is practically required to have a high hardness. In order to impart a high hardness to a rubber, heretofore, there have been carried out, for example, the addition of a large amount of carbon black in combination with a small amount of process oil, the addition of a reactive alkylphenol resin or the addition of a polyolefin.

EP-A-0 266 221 discloses a thermoplastic elastomer composition obtained by dynamically heat-treating a blend of a peroxide-crosslinking olefin copolymer rubber and an olefinic plastic with an unsaturated carboxylic acid or derivative thereof, an unsaturated epoxy monomer or an unsaturated hydroxy monomer in the presence of an organic peroxide and thereafter mixing the thus prepared partially crosslinked graft-modified polyolefin elastomer with an polyamide resin.

The present inventors have investigated a vulcanized, ethylene/α-olefin copolymer rubber composition having a high hardness and, as a result, found a novel vulcanized, ethylene/α-olefin copolymer rubber composition obtained by statically vulcanizing an unvulcanized rubber composition consisting essentially of an ethylene/α-olefin copolymer rubber; an ethylene/α-olefin copolymer rubber containing an α,β-unsaturated carboxylic acid and/or a derivative thereof; and a polyamide resin.

That is to say, the present invention relates to a vulcanized, ethylene/α-olefin copolymer rubber composition obtained by vulcanizing an unvulcanized rubber composition comprising 100 parts by weight of a rubber composition consisting of 0-99% by weight of an ethylene/α-olefin copolymer rubber and 100-1% by weight of an ethylene/α-olefin copolymer rubber containing 0.1-10% by weight of an α,β-unsaturated carboxylic acid and/or a derivative thereof based on the ethylene/α-olefin copolymer rubber containing the said carboxylic acid and/or a derivative thereof; and 5-100 parts by weight of a polyamide resin.

An object of the present invention is to provide a novel vulcanized, ethylene/α-olefin copolymer rubber composition having a high hardness.

Other objects and advantages of the present invention will become apparent from the following description.

In the present invention, the ethylene/α-olefin copolymer rubber (hereinafter referred to as EOR) is at least one selected from ethylene/α-olefin copolymers and ethylene/α-olefin/non-conjugated diene copolymers.

The α-olefin is preferably one having 3-10 carbon atoms and, specifically, includes propylene, 1-butene, 1-pentene or 1-hexene.

The non-conjugated diene includes, for example, dicylcopentadiene, ethylidenenorbornene, 1,4-hexadiene, methyltetrahydroindene or methylnorbornene.

The α,β-unsaturated carboxylic acid includes, for example, maleic acid, fumaric acid, itaconic acid, citraconic acid or nadic acid. The derivative thereof includes, for example, maleic anhydride, citraconic anhydride or nadic anhydride.

The ethylene/α-olefin copolymer rubber containing an α,β-unsaturated carboxylic acid and/or a derivative thereof (hereinafter referred to as the modified EOR) is produced according to the known process such as, for example, the graft copolymerization process stated in Japanese Patent Application Kokoku No. 58-53005 or Japanese Patent Application Kokoku No. 58-445.

Also, the modified EOR may contain an alkenyl aromatic monomer such as, for example, styrene or methylstyrene together with the α,β-unsaturated carboxylic acid and/or the derivative thereof each of which is produced according to the process stated in Japanese Patent Application Kokai No. 62-112614.

The content of the α,β-unsaturated carboxylic acid and/or the derivative thereof in the modified EOR is in a range of 0.1-10% by weight, preferably in a range of 0.3-7% by weight, more preferably in a range of 0.5-4% by weight, based on the modified EOR. When the content is smaller than 0.1% by weight, the enhancement of hardness is smaller. When, in contrast, the content is larger than 10% by weight, workability and the properties of the vulcanized rubber are deteriorated.

The polyamide resin is not particularly restricted and includes poly-ε-capramide (6-nylon), poly-Ω-undecaneamide (11-nylon), polyhexamethylene adipamide (6,6-nylon), polyhexamethylene sebacamide (6,10-nylon). The polyamide resin can be used irrespective of its molecular weight and whether or not it has amine groups.

The rubber composition comprising the EOR, the modified EOR and the polyamide resin is referred to as the unvulcanized rubber composition.

The content of the polyamide resin in the unvulcanized rubber composition is in a range of 5-100 parts by weight, preferably 10-80 parts by weight based on 100 parts by weight of the rubber compound consisting of 0-99% by weight, preferably 0-90% by weight of the EOR and 100-1% by weight, preferably 100-10% by weight of the modified EOR.

To the unvulcanized rubber composition, further, may be added an additive such as, for example, a reinforcing agent, a filler, a softening agent, a plasticizer, a processing aid, a vulcanization accelerator or a vulcanization agent, which are known in the rubber industry.

The unvulcanized rubber composition can be processed according to the conventional process in the rubber industry and can be vulcanized according to the conventional vulcanization process in the rubber industry. Thereby, there can be obtained the vulcanized, ethylene/α-olefin copolymer rubber composition of the present invention.

The vulcanized, ethylene/α-olefin copolymer rubber composition of the present invention can be used for automobile parts or industrial rubber parts.

The present invention will be explained more specifically below referring to Examples and Comparative Examples.

EXAMPLES 1-7 and COMPARATIVE EXAMPLES 1-4

A mixture prepared according to the formulation shown in column A of Table 1 was kneaded at a velocity of 60 rpm for 5 min at 250°C in a Brabender Plastograph having a kneading volume of 350 ml. After cooling, carbon black, process oil and stearic acid were added to the above mixture according to the formulation shown in column B of Table 1 and kneaded at a velocity of 60 rpm for 4 min in the Brabender Plastograph kept at a temperature of 100°C. To the resulting mixture, further, were added a vulcanization agent, a vulcanization accelerator and a vulcanization aid, using a 15.24 cm (6-in) roll according to the formulation shown in column C of Table 1 and kneaded. The resulting unvulcanized rubber composition was vulcanized by heating for 10 min at a temperature of 170°C using a vulcanizing press to obtain a sheet of the vulcanized rubber composition having a thickness of 2 mm. Physical properties of the vulcanized rubber composition were measured according to JIS K6301. Results are collectively shown in Table 1.

A vulcanized, ethylene/α-olefin copolymer rubber composition obtained by statically vulcanizing an unvulcanized rubber composition comprising 100 parts by weight of a rubber composition consisting of 0-99% by weight of an ethylene/α-olefin copolymer rubber and 100-1% by weight of an ethylene/α-olefin copolymer rubber containing 0.1-10% by weight of any of an α,β-unsaturated carboxylic acid, a derivative thereof or a mixture of an α,β-unsaturated carboxylic acid and a derivative thereof based on the ethylene/α-olefin copolymer rubber containing the unsaturated carboxylic acid and/or a derivative thereof; and 5-100 parts by weight of a polyamide resin, wherein an ethylene/α-olefin copolymer rubber is at least one selected from ethylene/α-olefin copolymers and ethylene/α-olefin/non-conjugated diene copolymers.

A vulcanized, ethylene/α-olefin copolymer rubber composition according to Claim 1, wherein the α-olefin has 3-10 carbon atoms.

A vulcanized, ethylene/α-olefin copolymer rubber composition according to Claim 1, wherein the α-olefin is selected from the group consisting of propylene, 1-butene, 1-pentene and 1-hexene.

A vulcanized, ethylene/α-olefin copolymer rubber composition according to Claim 1, wherein the non-conjugated diene is selected from the group consisting of dicyclopentadiene, ethylidenenorbornene, 1,4-hexadiene, methyltetrahydroindene and methylnorborne.

A vulcanized, ethylene/α-olefin copolymer rubber composition according to Claim 1, wherein the α,β-unsaturated carboxylic acid is selected from the group consisting of maleic acid, fumaric acid, itaconic acid, citraconic acid and nadic acid.

A vulcanized, ethylene/α-olefin copolymer rubber composition according to Claim 1, wherein the derivative of the α,β-unsaturated carboxylic acid is selected from the group consisting of maleic anhydride, citraconic anhydride and nadic anhydride.

A vulcanized, ethylene/α-olefin copolymer rubber composition according to Claim 1, wherein the polyamide resin is selected from the group consisting of poly-ε-capramide, poly-Ω-undecaneamide, polyhexamethylene adipamide and polyhexamethylene sebacamide.

A vulcanized, ethylene/α-olefin copolymer rubber composition according to Claim 1, wherein the unvulcanized rubber composition further contains at least one selected from the group consisting of a reinforcing agent, a filler, a softening agent, a plasticizer, a processing aid, a vulcanizing accelerator and a vulcanizing agent.

A process for preparing a vulcanized, ethylene/α-olefin copolymer rubber composition by statically vulcanizing an unvulcanized rubber composition comprising 100 parts by weight of a rubber composition consisting of 0-99% by weight of an ethylene/α-olefin copolymer rubber and 100-1% by weight of an ethylene/α-olefin copolymer rubber containing 0.1-10% by weight of any of an α,β-unsaturated carboxylic acid, a derivative thereof or a mixture of an α,β-unsaturated carboxylic acid and a derivative thereof based on the ethylene/α-olefin copolymer rubber containing the unsaturated carboxylic acid and/or a derivative thereof; and 5-100 parts by weight of a polyamide resin, wherein an ethylene/α-olefin copolymer rubber is at least one selected from ethylene/α-olefin copolymers and ethylene/α-olefin/non-conjugated diene copolymers.

A process according to Claim 1, wherein the α-olefin has 3-10 carbon atoms.

A process according to Claim 1, wherein the α-olefin is selected from the group consisting of propylene, 1-butene, 1-pentene and 1-hexene.

A process according to Claim 1, wherein the non-conjugated diene is selected from the group consisting of dicyclopentadiene, ethylidenenorbornene, 1,4-hexadiene, methyltetrahydroindene and methylnorbornene.

A process according to Claim 1, wherein the α,β-unsaturated carboxylic acid is selected from the group consisting of maleic acid, fumaric acid, itaconic acid, citraconic acid and nadic acid.

A process according to Claim 1, wherein the derivative of the α,β-unsaturated carboxylic acid is selected from the group consisting of maleic anhydride, citraconic anhydride and nadic anhydride.

A process according to Claim 1, wherein the polyamide resin is selected from the group consisting of poly-ε-capramide, poly-Ω-undecaneamide, polyhexamethylene adipamide and polyhexamethylene sebacamide.

A process according to Claim 1, wherein the unvulcanized rubber composition further contains at least one selected from the group consisting of a reinforcing agent, a filler, a softening agent, a plasticizer, a processing aid, a vulcanizing accelerator and a vulcanizing agent.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse, erhalten durch statisches Vulkanisieren einer nicht-vulkanisierten Kautschukmasse, umfassend 100 Gew.-Teile einer Kautschukmasse, die aus 0 - 99 Gew.-% eines Ethylen/α-Olefin-Copolymerkautschuks und 100 - 1 Gew.-% eines Ethylen/α-Olefin-Copolymerkautschuks mit 0,1 - 10 Gew.-% einer α,β-ungesättigten Carbonsäure, eines Derivats derselben oder eines Gemischs aus einer α,β-ungesättigten Carbonsäure und einem Derivat derselben, bezogen auf den Ethylen/α-Olefin-Copolymerkautschuk mit der ungesättigten Carbonsäure und/oder einem Derivat derselben, besteht, und 5 - 100 Gew.-Teile eines Polyamidharzes, wobei der Ethylen/α-Olefin-Copolymerkautschuk aus mindestens einem aus Ethylen/α-Olefin-Copolymeren und Ethylen/α-Olefin/nicht-konjugiertes Dien-Copolymeren ausgewählten Copolymerkautschuk besteht.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse nach Anspruch 1, wobei das α-Olefin 3 - 10 Kohlenstoffatome aufweist.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse nach Anspruch 1, wobei das α-Olefin aus der Gruppe Propylen, 1-Buten, 1-Penten und 1-Hexen ausgewählt ist.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse nach Anspruch 1, wobei das nicht-konjugierte Dien aus der Gruppe Dicyclopentadien, Ethylidennorbornen, 1,4-Hexadien, Methyltetrahydroinden und Methylnorbornen ausgewählt ist.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse nach Anspruch 1, wobei die α,β-ungesättigte Carbonsäure aus der Gruppe Maleinsäure, Fumarsäure, Itaconsäure, Citraconsäure und Nadinsäure ausgewählt ist.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse nach Anspruch 1, wobei das Derivat der α,β-ungesättigten Carbonsäure aus der Gruppe Maleinsäureanhydrid, Citraconsäureanhydrid und Nadinsäureanhydrid ausgewählt ist.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse nach Anspruch 1, wobei das Polyamidharz aus der Gruppe Poly-ε-capramid, Poly-Ω-undecanamid, Polyhexamethylenadipamid und Polyhexamethylensebacamid ausgewählt ist.

Vulkanisierte Ethylen/α-Olefin-Copolymerkautschukmasse nach Anspruch 1, wobei die nicht-vulkanisierte Kautschukmasse zusätzlich mindestens eine Komponente, ausgewählt aus der Gruppe Verstärkungsmittel, Füllstoff, Erweichungsmittel, Plastifizierungsmittel, Prozeßhilfsmittel, Vulkanisationsbeschleuniger und Vulkanisiermittel, enthält.

Verfahren zum Herstellen einer vulkanisierten Ethylen/α-Olefin-Copolymerkautschukmasse durch statisches Vulkanisieren einer nicht-vulkanisierten Kautchukmasse, umfassend 100 Gew.-Teile einer Kautschukmasse, die aus 0 - 99 Gew.-% eines Ethylen/α-Olefin-Copolymerkautschuks und 100 - 1 Gew.-% eines Ethylen/α-Olefin-Copolymerkautschuks mit 0,1 - 10 Gew.-% einer α,β-ungesättigten Carbonsäure, eines Derivats derselben oder eines Gemischs aus einer α,β-ungesättigten Carbonsäure und einem Derivat derselben, bezogen auf den Ethylen/α-Olefin-Copolymerkautschuk mit der ungesättigten Carbonsäure und/oder einem Derivat derselben, besteht, und 5 - 100 Gew.-Teile eines Polyamidharzes, wobei der Ethylen/α-Olefin-Copolymerkautschuk aus mindestens einem aus Ethylen/α-Olefin-Copolymeren und Ethylen/α-Olefin/nicht-konjugiertes Dien-Copolymeren ausgewählten Copolymerkautschuk besteht.

Verfahren nach Anspruch 1, wobei-das α-Olefin 3 - 10 Kohlenstoffatome aufweist.

Verfahren nach Anspruch 1, wobei das α-Olefin aus der Gruppe Propylen, 1-Buten, 1-Penten und 1-Hexen ausgewählt ist.

Verfahren nach Anspruch 1, wobei das nicht-konjugierte Dien aus der Gruppe Dicyclopentadien, Ethylidennorbornen, 1,4-Hexadien, Methyltetrahydroinden und Methylnorbornen ausgewählt ist.

Verfahren nach Anspruch 1, wobei die α,β-ungesättigte Carbonsäure aus der Gruppe Maleinsäure, Fumarsäure, Itaconsäure, Citraconsäure und Nadinsäure ausgewählt ist.

Verfahren nach Anspruch 1, wobei das Derivat der α,β-ungesättigten Carbonsäure aus der Gruppe Maleinsäureanhydrid, Citraconsäureanhydrid und Nadinsäureanhydrid ausgewählt ist.

Verfahren nach Anspruch 1, wobei das Polyamidharz aus der Gruppe Poly-ε-capramid, Poly-Ω-undecanamid, Polyhexamethylenadipamid und Polyhexamethylensebacamid ausgewählt ist.

Verfahren nach Anspruch 1, wobei die nicht-vulkanisierte Kautschukmasse zusätzlich mindestens eine Komponente, ausgewählt aus der Gruppe Verstärkungsmittel, Füllstoff, Erweichungsmittel, Plastifizierungsmittel, Prozeßhilfsmittel, Vulkanisationsbeschleuniger und Vulkanisiermittel, enthält.

Composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé, obtenue par vulcanisation statique d'une composition de caoutchouc non vulcanisé comprenant 100 parties en poids d'une composition de caoutchouc consistant en 0-99% en poids d'un caoutchouc de copolymère éthylène/α-oléfine et de 100-1% en poids d'un caoutchouc de copolymère éthylène/α-oléfine contenant 0,1-10% en poids d'un acide carboxylique α,β-insaturé, d'un de ses dérivés ou d'un mélange d'un acide carboxylique α,β-insaturé et d'un de ses dérivés, pourcentage exprimé par rapport au caoutchouc de copolymère éthylène/α-oléfine contenant l'acide carboxylique insaturé et/ou un de ses dérivés; et 5-100 parties en poids d'une résine de polyamide, composition dans laquelle un caoutchouc de copolymère éthylène/α-oléfine est au moins un choisi entre les copolymères éthylène/α-oléfine et les copolymères éthylène/α-oléfine/diène non conjugué.

Composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé selon la revendication 1, dans laquelle l'α-oléfine a de 3 à 10 atomes de carbone.

Composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé selon la revendication 1, dans laquelle l'α-oléfine est choisie dans le groupe comprenant le propylène, le 1-butène, le 1-pentène et le 1-hexène.

Composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé selon la revendication 1, dans laquelle le diène non conjugué est choisi dans le groupe comprenant le dicyclopentadiène, l,ethylidènenorbornène, le 1,4-hexadiène, le méthyltétrahydroindène et le méthylnorbornène.

Composition de caoutchouc copolymère éthylène/α-oléfine vulcanisé selon la revendication 1, dans laquelle l'acide carboxylique α,β-insaturé est choisi dans le groupe comprenant l'acide maléique, l'acide fumarique, l'acide itaconique, l'acide citraconique et l'acide nadique.

Composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé selon la revendication 1, dans laquelle le dérivé de l'acide carboxylique α,β-insaturé est choisi dans le groupe comprenant l'anhydride maléique, l'anhydride citraconique et l'anhydride nadique.

Composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé selon la revendication 1, dans laquelle la résine de polyamide est choisie dans le groupe comprenant le poly-ε-capramide, le poly-Ω-undécanamide, le polyhexaméthylène-adipamide et le polyhexaméthylène-sébaçamide.

Composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé selon la revendication 1, dans laquelle la composition de caoutchouc non vulcanisé contient en outre au moins un composant choisi dans le groupe comprenant les agents de renforcement, les charges, les agents de ramollissement, les plastifiants, les adjuvants de mise en oeuvre, les accélérateurs de vulcanisation et les agents de vulcanisation.

Procédé de préparation d'une composition de caoutchouc de copolymère éthylène/α-oléfine vulcanisé, par vulcanisation statique d'une composition de caoutchouc non vulcanisé comprenant 100 parties en poids d'une composition de caoutchouc consistant en 0-99% en poids d'un caoutchouc de copolymère éthylène/α-oléfine et de 100-1% en poids d'un caoutchouc de copolymère éthylène/α-oléfine contenant 0,1-10% en poids d'un acide carboxylique α,β-insaturé, d'un de ses dérivés ou d'un mélange d'un acide carboxylique α,β-insaturé et d'un de ses dérivés, pourcentage exprimé par rapport au caoutchouc de copolymère éthylène/α-oléfine contenant l'acide carboxylique insaturé et/ou un de ses dérivés; et 5-100 parties en poids d'une résine de polyamide, composition dans laquelle un caoutchouc de copolymère éthylène/α-oléfine est au moins un choisi entre les copolymères éthylène/α-oléfine et les copolymères éthylène/α-oléfine/diène non conjugué.

Procédé selon la revendication 1, dans lequel l'α-oléfine a de 3 à 10 atomes de carbone.

Procédé selon la revendication 1, dans lequel l'α-oléfine est choisie dans le groupe comprenant le propylène, le 1-butène, le 1-pentène et le 1-hexène.

Procédé selon la revendication 1, dans lequel le diène non conjugué est choisi dans le groupe comprenant le dicyclopentadiène, l'éthylidène-norbornène, le 1,4-hexadiène, le méthyltétrahydroindène et le méthylnorbornène.

Procédé selon la revendication 1, dans lequel l'acide carboxylique α,β-insaturé est choisi dans le groupe comprenant l'acide maléique, l'acide fumarique, l'acide itaconique, l'acide citraconique et l'acide nadique.

Procédé selon la revendication 1, dans lequel le dérivé de l'acide carboxylique α,β-insaturé est choisi dans le groupe comprenant l'anhydride maléique, l'anhydride citraconique et l'anhydride nadique.

Procédé selon la revendication 1, dans lequel la résine de polyamide est choisie dans le groupe comprenant le poly-ε-capramide, le poly-Ω-undécanamide, le polyhexaméthylène-adipamide et le polyhexaméthylène-sébaçamide.

Procédé selon la revendication 1, dans lequel la composition de caoutchouc non vulcanisé contient en outre au moins un composant choisi dans le groupe comprenant les agents de renforcement, les charges, les agents de ramollissement, les plastifiants, les adjuvants de mise en oeuvre, les accélérateurs de vulcanisation et les agents de vulcanisation.